Repellents for ants

ABSTRACT

A method has been discovered for repelling ants by treating objects or areas with effective amounts of compositions that include (a) one or more C 6  to C 8  carboxylic acids; (b) one or more C 6  to C 14  alcohols; (c) one or more esters which are reaction products of (a) and (b) or an ester which is a reaction product of the repellents and other carboxylic acids or alcohols; (d) one or more C 6  to C 11  carboxylic acid esters; (e) one or more C 6  to C 14  ketones; (f) one or more C 6  to C 14  aldehydes; or (g) mixtures thereof.

This application is a continuation-in-part of application Ser. No.08/235,848, filed on Apr. 29, 1994, now abandoned, which is acontinuation-in-part of application Ser. No. 07/925,685, filed Aug. 7,1992, now abandoned, which is herein incorporated by reference in itsentirety.

FIELD OF THE INVENTION

The present invention relates to repellent compositions for ants,particularly fire ants. The composition comprises an effective amount ofa repellent selected from: (i) one or more C₆ to C₁₄ alcohols; (ii) oneor more C₆ to C₈ carboxylic acids; (iii) one or more C₆ to C₁₁carboxylic acid esters; (iv) one or more C₆ to C₁₄ ketones; (v) one ormore C₆ to C₁₄ aldehydes; and (vi) mixtures thereof.

BACKGROUND OF THE INVENTION

Various species of ants pose significant problems for man from both aneconomic and a health care point of view. For example, leaf-cutting antspecies are a problem in Central and South America, where they candefoliate a citrus tree overnight. Consequently, a non-toxic repellentthat would prevent leaf-cutting ants from getting into the trees wouldbe of significant value. Also, in the southern United States, fire ants,Solenopsis invicta, are a substantial pest. For example, foraging fireants are known to destroy young citrus trees, growing crops, andgerminating seeds. This has an economic impact on agriculture ininfested areas. Telephone companies spend substantial amounts of moneyeach year on treating their electrical equipment to prevent fire antinvasion because fire ants are attracted to electrical fields and canshort out electrical equipment. Further, farm equipment can be damagedby large fire ant mounds. Fire ants also present a problem to wildlife,such as with ground nesting birds and animals. Furthermore, Fire antsare known to excavate the soil from under roadways causing damage.

Fire ants also pose a health care problem to the millions of peoplestung each year--a significant number of which require medical care.Further, fire ant stings are also blamed for human deaths each year.Consequently, there is much interest in controlling these troublesomeinsects.

This interest has resulted in much research and resources being expendedthrough the years to develop reagents and methods for controlling fireants. While many useful insecticide formulations have resulted from thisresearch, the problems associated with ants still exist. This isprimarily because the relief gained by insecticide use is only temporaryowing to the high reproductive capabilities, the efficient foragingbehavior, and the ecological adaptability, of ants. While effective forcontrolling ants in relatively small defined areas, the use ofinsecticides, because of their toxicity, can create other problems. Forexample, some insecticides, which are effective for controlling ants,are banned from use because they pose a significant threat to theenvironment, including birds and animals. Furthermore, there is pressurefrom environmental groups to stop, or at least substantially reduce, theapplication of insecticides in general, and to develop non-toxicreagents for controlling insects. One type of reagent which would be ofgreat interest would be a non-toxic reagent which could repel, or keepants from invading a particular area or object.

Such a reagent would be of great value in preventing leaf-cutting antsfrom attacking citrus and other agriculturally important trees. It wouldalso be of great value for preventing fire ants from attacking variousbiological control agents, such as parasitic wasps, which are used tocontrol a host of crop pests, including those which are harmful tocotton. The parasitic wasps are distributed as pupae in small capsuleswhich are dispersed in the area to be controlled. Adult wasps emergefrom the capsule within a matter of days. If the capsules aredistributed in an area infested with fire ants, the capsules are quicklyfound by foraging ants which penetrate the capsule and eat the wasp inits pupal stage--thus greatly decreasing the effectiveness of the use ofsuch biological control agents.

Therefore, there is still a substantial need in the art for reagents,particularly non-toxic reagents, which can be used to prevent ants frominvading a particular area or object.

SUMMARY OF THE INVENTION

In accordance with the present invention there is provided a repellentcomposition for ants, which composition is comprised of: (i) aneffective amount of one or more repellents selected from the groupconsisting of:

(a) one or more C₆ to C₈ carboxylic acids;

(b) one or more C₆ to C₁₄ alcohols represented by the formula: ##STR1##where R₁ is a C₁ to C₅ alkyl group, optionally containing olefinic,acetylenic, or aryl moieties; and R₂ is a C₂ to C₁₃ alkyl group,optionally containing olefinic, acetylenic, or aryl moieties;

(c) one or more C₆ to C₁₄ ketones represented by the formula: ##STR2##where R₁ is H or a C₁ to C₅ alkyl group optionally containing olefinic,acetylenic, or aryl moieties; and R₂ is a C₂ to C₁₃ alkyl groupoptionally containing olefinic, acetylenic, or aryl moieties;

(d) one or more C₆ to C₁₁ carboxylic acid esters represented by theformula: ##STR3## where R₁ is a C₂ to C₁₃ alkyl group optionallycontaining olefinic, acetylenic, aryl, or carboxylic acid ester moietiesand R₂ is a C₂ to C₁₃ alkyl group optionally containing olefinic,acetylenic, or aryl moieties;

(e) one or more C₆ to C₁₄ aldehydes represented by the formula: ##STR4##where R₁ is a C₆ to C₁₃ alkyl group optionally containing olefinc,acetylenic or aryl moieties;

(f) mixtures thereof; and

(ii) a carrier material.

Also in accordance with the present invention, there is provided arepellent composition for ants which is comprised of: (i) a derivativewhich is an ester that is a reaction product of an alcohol and acarboxylic acid, wherein at least the alcohol or the carboxylic acid isa repellent which meets one of the above formulae; and (ii) a carriermaterial.

Still in accordance with the present invention is a repellentcomposition for ants which is comprised of a (i) polymer compositionhaving pendent functional groups, capable of reaction with therepellent, selected from the group consisting of carboxylic acid groups,--OH groups and mixtures thereof; and (ii) the repellents covalentlybonded to the reactive groups.

Also in accordance with the present invention is a method for repellingants from an area or object, which method comprises treating said areaor object with an effective amount of a repellent composition selectedfrom the above mentioned carboxylic acids, alcohols, ketones, aldehydes,and esters.

In a preferred embodiment of the present invention, there is provided aneffective amount of the above compositions and a controlled releasematrix.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a bar graph of the percent response of ants placed in a Y-tubeolfactometer wherein one of the chambers has the test sample at aconcentration of 0.1% weight to volume. C₃ to C₁₈ straight chaincarboxylic acids were tested. A response of 35% or less is consideredrepellent.

FIG. 2 is a bar graph of laboratory tests of the repellent effects ofoctanoic acid against fire ant invasion of Trichogramma releasecapsules.

FIG. 3 is a bar graph of field tests of the repellent effects ofoctanoic acid against fire ants when the acid is impregnated onTrichogramma release capsules (treated on either the outside or inside).

FIG. 4 is a bar graph of the efficacy of various concentrations ofoctanoic acid to prevent fire ant workers from moving into treated pots.

*Experiment terminated.

FIG. 5 is a bar graph of the efficacy of various concentrations ofoctanoic acid to prevent fire ant workers from moving into treated potsfor up to 60 days.

FIG. 6 is a bar graph of the effects of aging treated peat pots prior toexposure to fire ant colonies.

FIG. 7 is a bar graph of the repellent effects of octanoic acid inacetone or lacquer painted onto the lower half and bottom of plasticpots.

FIG. 8 is a bar graph of the effect of octanoic acid/soil on a newlymated queen's choice of where to found her colonies. C-A and C-B arecontrols.

FIG. 9 is a graph of the percent response of ants placed in a Y-tubeolfactometer wherein one of the chambers has Avon's SKIN-SO-SOFT® byitself and at several dilutions with hexane.

DETAILED DESCRIPTION OF THE INVENTION

Preferred carboxylic acids suitable for use in the present inventioninclude octanoic acid, 2-methyl-hexanoic acid, and trans-2-hexenoicacid. More preferred is octanoic acid.

Non-limiting examples of alcohols which are suitable for use in thepresent invention include those selected from the group consisting of1-Octyn-3-ol, 1-Octen-3-ol, 4-Octanol, 2-Octen-4-ol, 3-Octen-2-ol,3-Octen-1-ol, 1-Hepten-3-ol, 1-Heptyn-3-ol, 2-Octanol, linalool,1-Nonen-3-ol, 3-Octanol, 2-Octen-1-ol, tetrahydrolinalool,(Z)-5-Octen-1-ol, and 1-Octanol.

A non-limiting example of ketones which are suitable for use in thepresent invention are 1-Octyn-3-one, 1-Octen-3-one, 4-Octanone,2-Octen-4-one, 3-Octen-2-one, 1-Hepten-3-one, 1-Heptyn-3-one,2-Octanone, 3-Octen-3-one, 1-Nonen-3-one, 3-Octanone, 2-Heptanone,2-Nonanone, and 2-Dodecanone.

A non-limiting example of aldehydes which are suitable for use in thepresent invention are Octanal, 3-Octenal, 5-Octenal, 2-Octenal,Heptanal, Nonanal, Decanal, and Tetradecanal.

Non-limiting examples of carboxylic acid esters which are suitable foruse in the present invention include those selected from the groupconsisting of 1-Nonen-3-yl acetate,Ethyl-2-hydroxy-3-phenyl-3-butenoate, bis-(6-methylheptyl) adipate, andbis-(1-methylheptyl) adipate. The bis-(1-methylheptyl) adipate can be inthe form of dilutions of Avon's SKIN-SO-SOFT® bath oil in solventranging from approximately about 100% SKIN-SO-SOFT® to approximatelyabout a 1:100 volume/volume of SKIN-SO-SOFT® and a liquid carriersuitable for repellent activity.

Derivatives of the carboxylic acid and alcohol repellents of the presentinvention may also be used. An example of a type of derivative which isparticularly suitable are esters which are the reaction product of analcohol and a carboxylic acid, one or both of which are repellents ofthe present invention. It is preferred that both the alcohol and thecarboxylic acid portion of the ester be repellents of the presentinvention. The ester ##STR5## is the reaction product of R--COOH and##STR6## wherein R is a C₅ to C₇ branched or straight chain alkyl group;R₁ is H or a C₁ to C₆ alkyl group, optionally containing olefinic,acetylenic, or aryl moieties, and R₂ is a C₂ to C₁₃ alkyl group,optionally containing olefinic, acetylenic, or aryl moieties, whereinthe carboxylic acid is a C₆ to C₈ carboxylic acid and the alcohol is aC₆ to C₁₄ alcohol. Upon hydrolysis, the ester will decompose and give upboth the alcohol and carboxylic acid repellent. An advantage to using anester is that the ester will most likely be less volatile because of itshigher molecular weight. Furthermore, hydrolysis of the ester wouldprovide a slow release of the repellent compounds.

Another type of derivative, called a pendent repellent, which issuitable for use herein, are polymers which contain an effective amountof pendent reactive groups capable of reaction with the repellentsselected from carboxylic acid groups and --OH groups or mixtures thereofto which the repellents are attached. Non-limiting examples of polymerssuitable for use herein include polyamides, polyesters, polyurethanes,and polyalkenes. The polymer having the acid and/or --OH groups will beused in combination with a repellent of the present invention so thatthe repellent will react with one or more of the acid or --OH groups ofthe polymer, thereby forming esters which are pendent on the polymerbackbone (McCormick et al, Controlled Release Pesticides, ACS SymposiumSeries, Vol. 53, pp. 112-125, 1977; Harris et al, Controlled ReleasePesticides, ACS Symposium Series, Vol. 53, pp. 102-111, 1977;Cardarelli, Controlled Release Polymeric Applications, ACS SymposiumSeries, Vol. 33, pp. 208-214, 1976; Meyers et al, Proc. Int. Symp.Controlled Release Restic. Pharm., Plenum, N.Y., pp. 171-190, 1981. AllIncorporated herein by Reference). Upon subsequent hydrolysis, arepellent carboxylic acid, alcohol, or both, will be released. The rateof hydrolysis can be controlled by adjusting the length of the pendentacid or --OH moiety in the polymer. Hydrolysis can occur under bothbasic and acidic conditions; e.g., in the soil. This type of derivativewill yield a solid formulation which is readily distributed whereneeded. The pendent repellent can be mixed with soil and used withnursery stock.

It is preferred for commercial applications that the repellents of thepresent invention be applied with a carrier component. The carriercomponent can be a liquid or a solid material. Liquids suitable ascarriers for the repellents of the present invention include both waterand organic solvents. Non-limiting examples of organic solvents suitablefor use in the present invention include acetone, hexane, lacquer,methanol, and methylene chloride. While most of the reagents of thepresent invention are not particularly soluble in water, they will forma suspension, or emulsion, in water which will be relatively stable andwhich will be suitable for applying to an area or object to be treated.It is more preferred that the repellent be soluble in the liquidcarrier. The amount of repellent used will be at least an effectiveamount. The term "effective amount", as used herein, means that minimumamount of repellent needed to repel, or substantially prevent the antsfrom invading a treated area or object, when compared to the same areaor object which is untreated. Of course, the precise amount needed willvary in accordance with the particular repellent composition used; thetype of area or object to be treated; the number of days of repellencyneeded; and the environment in which the area or object is located. Forexample, if the object or area to be treated is situated outdoors and isexposed to the weather, then higher concentrations of repellent would beneeded to be effective for a given period of time than if the objectwere indoors or under cover. The precise amount of repellent needed caneasily be determined by one having ordinary skill in the art given theteaching of this application. The examples herein show typicalconcentrations which will be needed to repel ants, particularly fireants.

Non-limiting examples of solid carrier materials which can be used inthe practice of the present invention include diatomaceous earth,alumina, silica, clays, other suitable inorganic oxides, as well aspowdered carbohydrates, such as corn starch, dextrans, and cellulose.The carrier may also be a solid substance, preferably one which willslowly release the repellent composition over a period of time.Non-limiting examples of slow release materials which are suitable foruse herein include latex particles, capillary tubes, andmicroencapsulation. Of course, the type of area or object to be treated,and the degree of infestation in the vicinity of the area, or object tobe treated, will dictate the type of carrier to be used. For example,when the object to be treated is a pot containing soil for nurserystock, it is preferred to use an aqueous suspension of the repellent.

The repellent compositions of the present invention can be combined withthe solid carrier material by any appropriate means. For example, theymay be combined by first dissolving or suspending, the repellent in asuitable solvent or other liquid; soaking the solid carrier materialwith the resulting solution or suspension, thereby either impregnatingthe repellent into, or depositing it onto, said solid carrier material;and, drying said treated carrier material to drive-off the solvent, orother liquid. The resulting repellent material can then be applied inpowder form, for example, by spraying the area or object to be treated.

Having thus described the invention and its preferred embodiments, thefollowing examples are presented to illustrate various embodiments ofthe present invention and should not be considered as limiting in anyway.

EXAMPLE 1

0.1% wt.:vol. hexane solutions were prepared for each of a homologousseries of C₃ to C₁₈ straight chain carboxylic acids. Each solution wasplaced in a Y-tube olfactometer. The olfactometer used herein is the onedescribed in Isolation of the Trail Recruitment Pheromone of Solenopsisinvicta, by R. K. Vander Meer, F. Alvarez, and C. S. Lofgren, Journal ofChemical Ecology, Vol. 14, No.3, pp. 825-838, 1988, and which isincorporated herein by reference.

The Y-tube olfactometer is comprised of two 24/40 ground glass jointswherein each ring is sealed to one of the arms of a 5 cm Y-tube suchthat 1 cm of each Y-tube arm extends through the male half of one of theground glass joints. A 5 cm piece of 0.6 cm ID tubing is ring sealed 1cm into the female half of the ground glass joints. A baffle is providedat the center of the Y tube for controlling air streams and to preventpremature mixing of the sample. It also gives the ants a clearer choice.The baffle also narrows the openings to the choice chambers to theminimum size required for passage of a major ant worker. A test sample(10 l/worker equivalent) and a solvent blank (101) were each applied toa separate filter paper strip (0.3×2.5 cm, Whatman No. 1). Each was airdried and one was placed in one of the choice chambers and the other inthe other chamber. Compressed air (breathing air quality) was split intotwo streams and passed into the two chambers. Each stream was regulatedto 0.2 liters/min. for a total effluent flow rate of 0.4 liters/min.Approximately 50 to 70 ants from laboratory colonies were confined in a2.5 cm piece of 0.9 cm ID Tygon tubing which was sealed at one end withwire gauze. The open end of the tubing was attached to the entrance stemleading to both chambers.

The initial choice of the first 20 ants that walked down the entrancetube and into one of the arms (chambers) of the Y tube was recorded.Ants that were not trapped in a chamber and came back to the entrancestem were not counted if they made another choice. After each test, theolfactometer was rinsed with acetone and dried. Each test sample wasretested with worker ants from the same colony, but the choice chamberin which the sample and control were placed was reversed. This procedureeliminated any bias inherent in the olfactometer. A complete replicatewas the sum of the results from the two tests. Data were analyzedstatistically by a chi-squared test. The results are shown in Table Ibelow and FIG. 1.

                  TABLE I                                                         ______________________________________                                        Acid Chain Length                                                                             % Response                                                    ______________________________________                                         3              46.8 ± 3.6                                                  4              48.3 ± 3.3                                                  5              55.8 ± 2.2                                                  6              50.8 ± 1.7                                                  7              50.8 ± 2.2                                                  8              34.2 ± 1.7                                                  9              45.0 ± 2.0                                                 10              40.8 ± 2.2                                                 11              48.3 ± 2.2                                                 12              46.6 ± 2.2                                                 13              43.3 ± 2.2                                                 14              50.0 ± 2.9                                                 15              50.0 ± 2.5                                                 16              51.6 ± 3.0                                                 17              48.3 ± 2.2                                                 18              49.2 ± 5.5                                                 ______________________________________                                    

Solutions which received greater than a 65% response are consideredattractants. Those which received a 35% or less response are consideredrepellents, and those between 35% and 65% are considered neutral. Theabove Table evidences that only the C₈ straight chain carboxylic acid,octanoic acid, was effective for repelling ants at a 0.1% weight:volumeconcentration.

EXAMPLE 2

1.0% weight:volume hexane solutions of 2-methylhexanoic acid andtrans-2-hexanoic acid were prepared and the procedure of Example 1 abovewas repeated. The results are shown in Table II below.

                  TABLE II                                                        ______________________________________                                        Carboxylic Acid  % Response                                                   ______________________________________                                        2-methylhexanoic acid                                                                          8.1 ± 3.2                                                 trans-2-hexanoic acid                                                                          10.0 ± 2.5                                                ______________________________________                                    

EXAMPLE 3

A series of experiments were performed to test the effect of octanoicacid for preventing predation on parasites in capsules used inbiological control programs. Trichogramma, a parasitic wasp bio-controlagent, used against cotton pests, is released as pupae in small capsulesfrom which the adults emerge within three days. In fire ant infestedareas, the capsules are quickly found by foraging fire ants, penetrated,and the parasites eaten. Thus, such a bio-control agent is madeineffective. These experiments were designed to test whether or not theaddition of octanoic acid to the capsules would prevent the ants fromentering the capsules long enough to allow adult parasites to emerge.

The inner surfaces of five Trichogramma release capsules were treatedwith 200 uL of a 5% wt.:vol. solution of octanoic acid in acetone. Theouter surfaces of another five capsules were treated with 200 uL of thesame solution, and an additional five capsules were untreated. Five flypupae were added to each of the 15 capsules, and the capsules weresealed with paraffin wax. Five fire ant colonies no larger then one (1)cell size were selected as test colonies. Each colony received a capsuletreated on the inside, a capsule treated on the outside, and anuntreated capsule. The capsules were placed approximately 10 cm from theperimeter of the colony cell. The response of the worker ants wasmonitored at 10 min and every hour thereafter for 5 hours. The capsuleswere then monitored daily at the following times from the beginning ofthe experiment: 1, 2, 3, 4, 7, 9, 11, and 16 days. On the fourth day,the colonies were fed for the first time since the start of theexperiment.

It was observed that worker ants entered all control (untreated)capsules within one hour (3 by 5 min. and 2 by 1 hour). One capsuletreated on the outside was invaded after 4 days, and by 9 days all fivereplicates had worker ants in them. The first invasion of a capsuletreated on the inside occurred at seven days posttreatment. By 16 daystwo capsules had not been invaded. The experiment was terminated after16 days. See FIG. 2.

EXAMPLE 4

The above experiment was repeated except that live flies were placedinside of the capsules to give the ants incentive to invade thecapsules. The capsules were tested in a field infested with fire ants.Part of the field was marked into an eight by eight meter grid,providing 64 possible capsule locations. The 15 capsules were randomlyplaced in the grid locations. It was found that all of the five controlcapsules were invaded by ants within the first hour of testing. At theend of 5 days none of the capsules which were treated on the outsidewere invaded, and only 1 of the capsules which was treated on the insidewas invaded. By the end of 9 days only three of the inside treated andthree of the outside treated capsules were invaded. The experiment wasstopped after 9 days. Thus, it can be clearly seen that octanoic acid iseffective in protecting the capsules from fire ant invasion for a longenough period of time to allow Trichogramma parasitic wasps to emergefrom the release capsules. See FIG. 3.

EXAMPLE 5

A series of experiments was performed to test the effect of a repellentof the present invention, octanoic acid, for preventing invasion of fireants in nursery plants.

Peat pots (75 mL) were treated with various concentrations of octanoicacid solutions in acetone, as set forth in Table III below. Theconcentrations ranged from about 0.01% to 50% wt.:vol. A control wasalso used which contained no octanoic acid. The samples were made byadding the appropriate volume of acetone to a known weight of octanoicacid, rather than by serial dilution. An application of 20 mL per potresulted in complete wetting of the peat pot. The pots were allowed todry in a fume hood for one hour, filled with moist nursery pottingmedia, and then placed in metal trays (19×30×5 cm) containing smallqueen-right fire ant colonies (ca. 1,000 workers and five mL ofimmatures and a queen). There were three replicates for the control andeach of the treatments. The pots were examined for ant invasion at 4 hr,24 hr, and at the end of two weeks. The results are set forth in TableIII below and FIG. 4.

                  TABLE III                                                       ______________________________________                                        % Weight:Volume                                                               Octanoic acid   Days to Invasion                                              ______________________________________                                         0.01           <0.16 ± 0.0                                                 0.1             <0.72 ± 0.48                                               1.0             <5.0 ± 3.5                                                10.0             >9.7 ± 7.5                                                50.0            >14.0 ± 0.0                                                Control         <0.16 ± 0.0                                                ______________________________________                                    

The above table shows that the two untreated pots were invaded withinfour hours. It also shows that increasing concentrations of octanoicacid gave increasing longevity of repellent activity. At the highestconcentration, no ants had invaded the pots at the end of two weeks.

EXAMPLE 6

Additional concentrations of octanoic acid in acetone were prepared andthe procedure of Example 4 above was repeated except that there werefive replicates of each treatment and a control. The experiment wasmonitored after 4 hr, 24 hr, then on a weekly basis for a total of eightweeks, at which time the experiment was terminated. The results are setforth in Table IV below and FIG. 5.

                  TABLE IV                                                        ______________________________________                                        % Weight:Volume                                                               Octanoic Acid   Days to Invasion                                              ______________________________________                                        0.5              <7.0 ± 0.0                                                 0.75            <7.5 ± 4.9                                                1.0             <12.25 ± 3.5                                               2.5             <14.0 ± 0.0                                                5.0             <18.2 ± 3.8                                                7.5             <28.0 ± 8.6                                                10.0            <39.2 ± 6.3                                                50.0            >56.0 ± 0.0                                                Control          <0.16 ± 0.062                                             ______________________________________                                    

The above table shows that octanoic acid repelled ants for increasinglengths of time with increasing concentrations. For example, the 10%solution had a mean repellent life of between 26 days and 38 days. Onlyone of the five 50% treatments was invaded by ants after 56 days, whenthe experiment ended.

EXAMPLE 7

A series of experiments were carried out to test the effectiveness ofoctanoic acid for repelling fire ants from peat pots when subjected tothe outdoor elements. Concentrations of 10% wt.:vol. and 50% wt.:vol..octanoic acid in acetone solutions were prepared and applied to peatpots as described in the previous examples. The treated pots were filledwith moist soil and exposed to the elements outdoors. After each of 0,7, 14, 28, and 56 days, three pots were taken to the laboratory andevaluated for repellent activity against laboratory fire ant colonies.It was observed that all treatments of 50% octanoic acid kept 100% ofthe ants away through 28 days of aging. Between 28 days and 56 days,there were heavy rains (>5 inches), which may explain the lack of anyrepellency at 56 days of aging. See FIG. 6.

EXAMPLE 8

Instead of peat pots, which readily absorb the octanoic acid solutions,plastic nursery pots were used. Two octanoic acid treatments wereevaluated: a) octanoic acid in acetone, and b) octanoic acid in lacquer.The two controls were acetone, and acetone plus lacquer. All except theacetone control were formulated as 1 to 1 solutions. The lower half andbottom of the pots were painted with the solutions. The pots wereobserved for fire ant invasion and the results are set forth in Table Vbelow and FIG. 7.

                  TABLE V                                                         ______________________________________                                        Treatment        Days to Invasion                                             ______________________________________                                        Octanoic Acid     1.33 ± 0.33                                              Lacquer          0.17 ± 0.0                                                Octanoic Acid + Lacquer                                                                         5.0 ± 1.53                                               Control          0.17 ± 0.0                                                ______________________________________                                    

The above table shows that octanoic acid by itself had significantrepellent activity, but more interesting are the results from thecombination of lacquer and octanoic acid. It appears as if the lacquerslows the loss of octanoic acid, thus extending its effectiveness. Theseresults evidence to the potential of the repellent in controlled releaseformulations.

EXAMPLE 9

A four choice soil bioassay was devised that allowed the determinationof whether or not newly mated queen fire ants would discriminate betweensoils in which to build their nuptial chamber (found a colony). Twocontrol choices (soil plus water) and two treatment choices were used.The treatments were: (i) soil plus octanoic acid at 0.26% (W/W) and (ii)soil plus octanoic acid at 1.3% (W/W). Three newly mated queen fire antswere placed in the middle of each of the four choice quadrants. Theycould move freely from one quadrant to the other. There were fourreplicates. After three days the soil from each quadrant was removed andsearched for queens.

It was observed that only one of the 48 queens released into the fourreplicates chose one of the octanoic acid treated quadrants. All otherspicked the control soil. These results indicate that it is possible toexclude newly mated queens from an area using octanoic acid as arepellent. See FIG. 8.

EXAMPLE 10

The procedure of Example 1 above was followed for different chemicals ateither a 1% weight:volume or 0.1% weight:volume concentration. Theresults are shown in Table VI below.

                  TABLE VI                                                        ______________________________________                                                              Conc.                                                   Number   Chemical Name                                                                              (% weight:volume)                                                                          Response %                                 ______________________________________                                        Not assigned                                                                           1-heptanol   1.0           15 ± 6.6                               Not assigned                                                                           2-heptanol   1.0           20 ± 4.3                               Not assigned                                                                           S(+) 2-octanol                                                                             1.0            5 ± 2.5                               Not assigned                                                                           1-nonanol    1.0            5 ± 2.5                               Not assigned                                                                           2-nonanol    1.0          1.7 ± 1.4                               Not assigned                                                                           1-decanol    1.0          3.3 ± 3.8                               Not assigned                                                                           1-dodecanol  1.0          38.3 ± 17.7                             Not assigned                                                                           2-dodecanol  1.0           25 ± 7.5                               Not assigned                                                                           1-tetradecanol                                                                             1.0          33.3 ± 2.8                              Not assigned                                                                           2-tetradecanol                                                                             1.0          45.8 ± 7.2                              82521-a  1-Octyn-3-ol 1.0           10 ± 5.0                               Not assigned                                                                           1-Octen-3-ol 1.0           10 ± 2.5                               37214    4-Octanol    1.0          14.2 ± 5.2                              28628    2-Octen-4-ol 1.0          15.8 ± 5.77                             39568-a  3-Octen-2-ol 1.0          16.6 ± 2.88                             39566-a  3-Octen-1-ol 1.0          16.6 ± 5.20                             28621    1-Hepten-3-ol                                                                              1.0          17.5 ± 2.5                              37262    1-Heptyn-3-ol                                                                              1.0          17.5 ± 5.0                              5589     2-Octanol    1.0            20 ± 3.81                             36553    1-Nonen-3-yl 1.0          24.2 ± 3.81                                      acetate                                                              942      Linalool     1.0          25.8 ± 3.81                             54065    3-Octen-2-one                                                                              1.0          26.6 ± 3.81                             8-60A    1-Nonen-3-ol 1.0          28.3 ± 6.29                             37213    3-Octanol    1.0          28.3 ± 12.5                             36043-a  2-Octen-1-ol 1.0          29.3 ± 5.77                             24903    Tetrahydrolinalool                                                                         1.0          29.2 ± 3.81                             TPM 10-109                                                                             Ethyl 2-hydroxy-3                                                                          1.0            30 ± 2.50                                      phenyl-3-butenoate                                                   39567    (Z)-5-Octen-1-ol                                                                           1.0          31.6 ± 1.44                             2169     1-Octanol    1.0          33.3 ± 1.44                             TPM 10-152                                                                             2-Ethoxyethyl                                                                              1.0          34.2 ± 8.3                                       2-hydroxy 3-phenyl-                                                           3-butenoate                                                          TPM 10-127                                                                             Propyl 2-hydroxy-3-                                                                        1.0          39.2 ± 2.88                                      phenyl-3-butenoate                                                   34394    1-octen-3-yl acetate                                                                       1.0            40 ± 9.01                             TPM 10-158-2                                                                           3-methylbutyl 2-                                                                           1.0          40.8 ± 3.81                                      hydroxy-3-phenyl-                                                             3-butenoate                                                          10519    Nerolidol    1.0          42.5 ± 4.99                             TPM 10-133                                                                             Isopropyl 2- 1.0          42.5 ± 6.61                                      hydroxy-3-phenyl-                                                             3-butenoate                                                          TPM 10-150                                                                             Allyl 2-hydroxy-3-                                                                         1.0          45.8 ± 7.63                                      phenyl-3-butenoate                                                   28606    1-Penten-3-ol                                                                              1.0          47.5 ± 4.33                             TPM 10-62-2                                                                            Ethyl alpha- 1.0          47.5 ± 4.99                                      hydroxy-4-tert-                                                               butyl-1-cyclo-                                                                hexene-1-ylacetate                                                   28424-b  3-buten-2-ol 1.0          48.3 ± 3.81                             34096-x  Ethyl beta-chloro-                                                                         1.0          51.6 ± 2.88                                      alpha hydroxy-beta                                                            methylhydro-                                                                  cinnamate                                                            34090-x  Propyl beta-chloro-                                                                        1.0          56.6 ± 2.88                                      beta-ethyl-alpha                                                              hydroxyhydro-                                                                 cinnamate                                                            34097-x  Propyl beta-chloro-                                                                        1.0          59.1 ± 3.81                                      alpha-hydroxy-beta                                                            methyl-                                                                       hydrocinnamate                                                       TPM 10-63-2                                                                            Ethyl alpha- 1.0            60 ± 8.66                                      hydroxy-alpha-                                                                methyl-4-tert                                                                 butyl-1-cyclo-                                                                hexene-1-ylacetate                                                   Not assigned                                                                           10-undecenic acid                                                                          1.0          48.3 ± 3.8                              Not assigned                                                                           trans-traumatic acid                                                                       1.0          56.9 ± 8.8                              14312    Allyl alcohol                                                                              1.0          64.2 ± 5.77                             28628    2-Octen-4-ol 0.1          27.5 ± 6.61                             Not assigned                                                                           1-Octen-1-ol 0.1          31.6 ± 2.88                             39566    3-Octen-1-ol 0.1          32.5 ± 2.49                             82521    1-Octyn-3-ol 0.1          34.2 ± 5.2                              37262    1-Heptyn-3-ol                                                                              0.1           45 ± 7.5                               5598     2-Octanol    0.1          48.3 ± 3.81                             28621    1-Hepten-3-ol                                                                              0.1            50 ± 4.33                             37214    4-Octanol    0.1          51.6 ± 8.77                             Not assigned                                                                           2-Nonanone   1.0          17.5                                       Not assigned                                                                           Decanal      1.0          22.2                                       ______________________________________                                    

The reagents tested in this example which meet the requirements of thepresent invention for repelling ants are those having a % response equalto, or less than, 35%.

EXAMPLE 11

Avon's product SKIN-SO-SOFT® is known to be repellent to mosquitoes. Aseries of tests were carried out to determine its effectiveness forrepelling fire ants. Various concentrations of SKIN-SO-SOFT® bath oilwere tested, using hexane as a dilutent, in the olfactometer bioassaydescribed in Example 1. The results are shown in Table VII below andFIG. 9.

                  TABLE VII                                                       ______________________________________                                                                  OLFACTOMETER                                        COMPONENT       DILUTION  RESPONSE (%)                                        ______________________________________                                        SKIN-SO-SOFT ® bath oil                                                                   100.00%    31.3 ± 3.82                                     SKIN-SO-SOFT ® bath oil                                                                   1:3        27.5 ± 6.61                                     SKIN-SO-SOFT ® bath oil                                                                   1:10      28.33 ± 7.64                                     SKIN-SO-SOFT ® bath oil                                                                   1:30      25.83 ± 5.77                                     SKIN-SO-SOFT ® bath oil                                                                   1:100     25.00 ± 6.61                                     SKIN-SO-SOFT ® bath oil                                                                   1:300     35.00 ± 6.12                                     SKIN-SO-SOFT ® bath oil                                                                   1:1,000   43.75 ± 1.77                                     ______________________________________                                    

Dilutions in the range of approximately about 1:100 volume:volumeSKIN-SO-SOFT®:Hexane to approximately about 100%. SKIN-SO-SOFT® aresignificantly repellent for fire ants and meet the requirements of thepresent invention of having a percent response equal to, or less than,35%.

EXAMPLE 12

In order to determine which component(s) of the SKIN-SO-SOFT®composition was responsible for the repellent activity, each componentwas tested in an olfactometer bioassay, as described in Example 1, atits concentration in the SKIN-SO-SOFT® COMPOSITION. The composition ofSKIN-SO-SOFT® is 50% mineral oil, 24.45% isopropyl palmitate, 20.75%Di-(1-methylheptyl) adipate, 0.25% Dioctyl Na Sulfosuccinate, and 3.55%fragrance. All the compounds were purchased from a commercial vender(Aldrich Chem. Co., Milwaukee, Wis.) except for Bis-(1-methylheptyl)adipate which was synthesized and purified by standard esterificationmethodology analogous to the method disclosed for the synthesis ofdiethyl adipate disclosed in Elementary Practical Organic Chemistry,Part 1--Small Scale Preparations, A. I. Vogel, John Wiley & Sons, Inc.,N.Y., N.Y., pp. 191, 1957, which is herein incorporated by reference.The results are shown in Table VIII below.

                  TABLE VIII                                                      ______________________________________                                                                  OLFACTOMETER                                        COMPONENT       PERCENT   RESPONSE (%)                                        ______________________________________                                        Mineral oil     50.00     53.3 ± 3.82                                      Isopropyl Palmitate                                                                           25.45     51.7 ± 12.83                                     Di-(1-methylheptyl) Adipate                                                                   20.75     0.0 ± 0.0                                        Dioctyl Na Sulfosuccinate                                                                     0.25      55.0 ± 13.69                                     Fragrance       3.55      unknown                                             SKIN-SO-SOFT ® bath oil                                                                   100.00    31.3 ± 12.99                                     ______________________________________                                    

The C₆ dicarboxylic acid diester, Di-(1-methylheptyl) adipate, was theonly component to show significant repellent activity.

EXAMPLE 13

Based on the above finding, other diesters of dicarboxylic acids weretested as 1% (W/V) hexane solutions as described in Example 1. All thecompounds were purchased from a commercial vender (Aldrich Chem. Co.,Milwaukee, Wis.) except for Bis-(1-methylheptyl) adipate which wassynthesized and purified using standard esterification methodology. Theresults are presented in Table IX below.

                  TABLE IX                                                        ______________________________________                                                           OLFACTOMETER                                               COMPOUND           RESPONSE (%)                                               ______________________________________                                        A. Bis-n-octyl Adipate                                                                           57.5 ± 10.0                                             B. Bis-(6-methylheptyl) Adipate                                                                  11.7 ± 7.6                                              C. Bis-(1-methylheptyl) Adipate                                                                  0.0 ± 0.0                                               D. Bis-(2-ethylheptyl) Adipate                                                                   40.0                                                       ______________________________________                                    

It was found that Bis-(6-methylheptyl) Adipate was also significantlyrepellent to fire ants.

The foregoing detailed description is for the purpose of illustration.Such detail is solely for that purpose and those skilled in the art canmake variations therein without departing from the spirit and scope ofthe invention.

What is claimed is:
 1. A method for repelling fire ants from an objector area comprising treating the object or area with a fire ant repellingcomposition comprisinga fire ant repelling reagent which is a C₆ to C₁₁carboxylic acid ester selected from the group consisting of1-nonen-3-yl-acetate, ethyl-2-hydroxy-3-phenyl-3-butenoate,bis-(6-methylheptyl)adipate and bis-(1-methylheptyl) adipate, and acarrier material.